Method and apparatus for treating filamentary material



Aprll 26, 1949. w, KQSTER 2,468,081

METHOD AND APPARATUS FOR TREATING FILAMENTARY MATERIAL Filed Nov. 18, 1944 INVENTOR. I

BY w a, m

Patented Apr. 26, l94

METHOD AND APPARATUS. FOR TREATING FILAMENTARY MATERIAL Frederick. Koster, Wallingford; Pa assignor to American Viscose Corporation, Wilmington, Dela, a corporation of Delaware Application November 18, 1944;, SerialNo. 564,169

9:Claims-., 12

This invention is concerned with improvements in: or relating. to the treatment of textiles and other materials, and particularlywith improvements in processes and apparatus for the treatment of yarns and other materials in a closed chamber'with fluid media in vapor condition during their travel from one point to another. The invention: is particularly concerned with the utilization of such fluid media. for applying heat to such filamentary material; or for applying heat while simultaneously softening the textile mate.- riaL by virtue of a swelling: or solvent action of the vapors'thereupon, and the invention is of special advantage when applied for the purpose; of plasticizing: or softening. the: textile materials, especially when in the form of yarn-like bundles when it is desired: to stretch such materials in softened condition.v For this purpose; the invention is of" special; application. to=suchtextile materials as yarn-like bundles of filaments made of cellulose-derivatives and: resins; examples of" cellulose derivatives including cellulose acetate, cel-- lulose propionate, cellulose butyrate, cellulose: acetate propionate and cellulose acetate butyrate. Examples of. the resins include the vinyl resins, such as polyvinyl chloride, copolymers of vinyl chloride with vinyle acetate; or with acrylonit'rile after-chlorinated vinyl polymers and copolymers,v vinyliden'e: polymers: such as polyvinylidene' chlo-.- ride;. nylons, polyethylene, and the like;

Running yarns of suchimaterialshave hereto fore been subjectedrto fluids,- such as steam in aclosed chamberxprovidedwith inlet and outlet. orifices at. each end thereof; However, it is often desirable tomake. use. of such vaporous'fluids at temperatures. in excess of their saturation temperature at normal atmosphericpressure, in order to obtain higher temperatures in proximity to the yarn. When applying. such a vapor athigh pressure to obtain'higher saturation temperatures by' introducing it into the chamber through which the yarn is running, the pressure is limited by the presence: of the orifices through. which the: vapor escapes; In addition; the escape through the orifices occurs at extremely high speeds whichlimparts uncontrolled and secondary stretching effacts to the. yarn as it enters and as it leaves the chamber. It has heretofore been proposed to overcome thesedifiiculties-by providing additional chambers, one inadvance of the entrance to the main stretching chamber and one following such chamber, so that air or other cold fluid can be maintained'in theseauxiliarychambers at a pressure substantially equal to the pressure of thevaporwithin themainstretching chamber; This from the jacket and still in vaporousconditioir isdirected into the main chamber adjacent thematerial entrance: insuch a manner as to flow in the same direction through thechamberasthe' material. The flow of the fluid into the main chamber is controlled so that the velocity" of thefluid within the main'chamber is relatively low;

or if it is allowed to occur at high velocity, it is under substantial control and occurs concur rently with the material throughout its passage through the tube, so that there is substantially uniform treatment of the material by the fluid; The filamentary material may be preliminarily soaked in the liquid phase of the-fluid to the va'- pors of which it is to besubjected; or it may be soaked with a liquid solvent or swelling agent a just'b'efore entering the vapor tre'atmentcham her.

The invention is illustrated in connectionwith the accompanying drawing, in which th'esin'gle" figure is illustrative of a preferred embodimentof equipment for performing themethod of the invention;

As shown, the-material 2, in the form of a yarnlike-b'undle which may be composed of continu-' ousartificial filaments of a cellulose ester or ofa vinyl resin, passesaround a godet or wheel 3 and arr associated lap-displacing guide 4'through" a relativelynarrow' chamber or tube 5, preferably of good heat-conducting material, such as iron,- steel, copper, and the like, and about another godet or Wheel 6 and its associated as displacing guide I. as at 9" surrounds the chamber 5 and isprovided with a supply conduit I0 controlled by a valve- I I for directing the vaporousfluid into the annu' -lar chamber l2'in the jacket 8' and surrounding the tube 5; A connection I3 is providedfor'con ducting condensateinto a trap M from which it may be discharged through-the'conduit [53 A connection lt'isprovided between the high pres sure side-of the-trap M and there is an injector arrangement at H for directing the fluid intothe tube 5 concurrently with the material"; valve i8 is provided for controlling the'fiow" of' the fluid into the tube 5.

A jacket 8 well insulated-- The injectorco mpri'ses a tube Hi having a restricted internal diameter" for guiding the material into the tube 5 and an annular chamber 20 communicating at 2| with the conduit l6 and having an annular opening surrounding the tube l5 communicating with the entrance end of the tube 5. A nozzle 22 may be provided to apply a liquid to the material as it passes over the godet 3.

In operation, the fluid, e. g. steam, is introduced by the conduit Ill at any desired superatmospheric pressure, so that the temperature of the tube can be raised to any desired extent and the valve I8 can be controlled to permit any predetermined relatively small portion of the high pressure fluid to enter the injector ll and thence the tube 5. Adjacent the point of entrance to tube 5, a reduced pressure is developed within the tube I9 when the fluid passes through the chamber 20 at a considerable velocity because of high pressure in the chamber 12 and a small amount of outside atmosphere may be drawn into the tube 5 along with the material. However, the efiect of this air introduced is relatively negligible, and since the fluid flows concurrently with the material throughout its passage through the tube 5, it has a uniform and controlled action thereupon. The valve it can be so controlled that the fluid discharged from the exit end of the tube '5 flows at a relatively low velocity or high velocity as desired. At the same time, the thread can be maintained at the high temperature substantially throughout its passage through the tube, because of the fact that the steam bled through valve !8 into the tube 5 is thereafter heated by the steam in the jacket chamber I2. The godets may be driven at the same speed, or if stretching is desired as in the preferred case, the godet 6 may be driven at a higher speed than-the godet 3. The exit opening of the tube 5 may be restricted, or if the tube 5 is of relatively small diameter such as from A; to /2 inch, it may be left wide open without appreciably afiecting the results obtained. Cold or hot Water or a solvent or swelling liquid, such as acetone, ethyl acetate, and the like, may be applied to the material by the nozzle 22, if desired.

Where as in arrangements heretofore utilized without auxiliary end pressure chambers it has been found to be extremely diihcult to obtain temperatures as high as 125 to 130 C. when using steam at 30 pounds per square inch gauge pressure, it has been found possible with the system of the present invention to obtain much higher temperatures without any difiiculty whatsoever. Thus, steam under 60 pounds per square inch pressure may be supplied in the jacket to provide a tube temperature of about 153 C. It appears that the steam in the inner tube can actually be superheated. The tube and jacket, of course, can be designed to accommodate a fluid such as steam, under any pressure and temperature whatsoever within the strength characteristics of the materials, so that the system of the present invention can be utilized to obtain temperatures not heretofore obtained by the use of heated vapors. In addition, if high velocity steam is led into the tube from the jacket, it is controlled so that any stretching it exerts upon the material serves a useful purpose.

While the utilization of the apparatus has been described in connection with steam specifically, it is to be understood that the invention contemplates the use of other vapors, especially when it is necessary to use them at temperatures higher than their normal saturation temperature in order to obtain the particular temperature needed for the particular material treated. To obtain the higher temperature with any particular vapor, it may be supplied in the superheated condition under slightly higher pressure than atmospheric, or it may be supplied at high swperatmospheric pressures and either saturated or superheated with respect thereto. Examples of solvent vapors are acetone or acetone-air acetone-steam mixtures.

It is to be understood that changes and vari ations may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. A method of heating a strand comprising continuously passing the strand longitudinally through an elongated narrow channel having strand entrance and exit openings at its ends communicatin with the atmosphere whereby the pressure in the channel is approximately atmospheric, heating the channel by conduction from a heated vapor medium supplied continuously at superatm-ospheric pressure to a region surrounding the channel, and continuously directing a portion of the vapor medium discharged from the surrounding region into the channel adjacent the strand entrance as a stream entering the channel substantially concentrically about the strand entrance and controlling the velocity of the vapor medium as it enters the channel by limiting the quantity entering so that the flow of the medium in the channel occurs at low velocity and is substantially concurrent with the strand throughout its passage therethrough and the spent medium is discharged from the channel with the strand whereby escape of the vapor medium from the channel through the strand entrance is inhibited and the necessity of special sealing means is obviated.

2. A method of heating a strand comprising continuously passing the strand longitudinally through an elongated narrow channel having strand entrance and exit openings at its ends communicating with the atmosphere whereby the pressure in the channel is approximately atmospheric, heatin the channel by conduction from a substantially saturated vapor medium supplied continuously at superatmospheric pressure to a" region surrounding the channel, and continuously directing a portion of the vapor medium discharged from the surrounding region into the channel adjacent the strand entrance as a stream entering th channel substantially concentrically about the strand entrance and controlling the velocity of the vapor medium as it enters the channel by limiting the quantity entering so that the flow of the medium in the channel occurs at low velocity and is substantially concurrent with the strand throughout its passage therethrough and the spent medium is discharged from the channel with the strand whereby escape of the vapor medium from the channel through the strand entrance is inhibited and the necessity of special sealing means is obviated.

3. A method of. heating a strand comprising continuously passing the strand longitudinally through an elongated narrow channel having strand entrance and exit openings at its ends communicating with the atmosphere whereby the pressure in the channel is approximately atmospheric, heating the channel by conduction from steam supplied continuously at super-atmospheric pressure to a region surrounding the channel, and continuously directing a portion of the steam discharged from the surrounding region into the channel adjacent the strand entrance as a stream entering the channel substantially concentrically about the strand entrance and controlling the velocity of the steam as it enters the channel by limiting the quantity entering so that the flow of the steam in the channel occurs at low velocity and is substantially concurrent with the strand throughout its passage therethrough and the spent steam is discharged from the channel with the strand whereby escape of the steam from the channel through the strand entrance is inhibited and the necessity of special sealing means is obviated.

4. A method of heating a strand comprising continuously passing the strand longitudinally through an elongated narrow channel having strand entrance and exit openings at its ends communicating with the atmosphere whereby the pressure in the channel is approximately atmospheric, heating the channel by conduction from steam supplied continuously at superatmospheric pressure to a region surrounding the channel, and continuously directing a portion of the steam dis charged from the surrounding region into the channel adjacent the strand entrance as a stream entering the channel substantially concentrically about the strand entrance and controlling the velocity of the steam as it enters the channel by limiting the quantity entering so that the flow of the steam in the channel occurs at low velocity and it substantially concurrent with the strand throughout its passage therethrough and the spent steam is discharged from the channel with the strand whereby escape of the steam from the channel through the strand entrance is inhibited and the necessity of special sealing means is obviated, and stretching the strand during its passage through the channel.

5. A method of heating a strand comprising continuously passing the strand longitudinally through an elongated narrow channel having strand entrance and exit openings at its ends communicating with the atmosphere whereby the pressure in the channel is approximately atmospheric, heating the channel by conduction from substantially saturated steam supplied continuously at superatmospheric pressure to a region surrounding the channel, and continuously directing a portion of the steam discharged from the surrounding region into the channel adjacent the strand entrance as a stream entering the channel substantially concentrically about the strand entrance and controlling the velocity of the steam as it enters the channel by limiting the quantity entering so that the flow of the steam in the channel occurs at low velocity and is substantially concurrent with the strand throughout its passage therethrough and the spent steam is discharged from the channel with the strand whereby escape of the steam from the channel through the strand entrance is inhibited and the necessity of special sealing means is obviated.

6. Apparatus for heating a strand comprising an elongated narrow tube having a wall of conductive material having strand entrance and exit openings in opposite ends thereof, means for continuously passing a strand longitudinally in a straight path through the openings and the tube, a tubular guide disposed concentrically within the entrance opening to provide an annular passage therebetween, an enclosed jacket surrounding the wall of the tube for receiving a vapor medium under pressure therein, means for supplying a heated vapor medium to the jacket, the exit opening of the tube being arranged to discharge the medium therefrom externally of the jacket, and means for continuously directing a portion of the vapor medium from the jacket through the annular passage into the tube adjacent the strand entrance so that the floW of the medium in the tube is substantially concurrent with the strand throughout its passage therethrough.

7. Apparatus for heating a strand comprising an elongated narrow tube having a wall of conductive material having strand entrance and exit openings in opposite ends thereof, means for continuously passing a strand longitudinally in a straight path through the openings and the tube, an enclosed jacket surrounding the wall of the tube for receiving a vapor medium under pressure therein, means for supplying a heated vapor medium at superatmospheric pressure to the jacket, the exit opening of the tube being arranged to discharge the medium therefrom externally of the jacket, and means comprising a pressure-reducing valve for continuously direct-- ing a portion of the vapor medium from the jacket into the tube adjacent the strand entrance, said latter means constituting with the strand entrance an injector having an annular fluid passage surrounding the strand entrance so that the fiow of the medium in the tube is substantially concurrent with the strand throughout its passage therethrough.

8. Apparatus for heating a strand comprising an elongated narrow tube having a wall of conductive material having strand entrance and exit openings in opposite ends thereof, means for continuously passing a strand longitudinally in a straight path through the openings and the tube, an enclosed jacket surrounding the wall of the tube for receiving a vapor medium under pressure therein, means for supplying a heated vapor medium under pressure to the jacket, the exit opening of the tube being arranged to discharge the medium therefrom externally of the jacket, an injector jet at the entrance of the tube having a central opening to permit passage of the strand and an annular opening concentric with the central opening, a discharge conduit connected to the jacket, a branch conduit connected to the discharge conduit adjacent the connection of the latter to the jacket and connected to the annular opening of the jet for continuously directing a portion of the vapor medium from the jacket into the tube adjacent the strand entrance so that the flow of the vapor medium in the tube is substantially concurrent with the strand throughout its passage therethrough.

9. Apparatus in accordance with claim 8 in which a pressure-reducing valve is provided in the branch conduit for controlling the flow of the vapor medium into the tube.

FREDERICK W. KOSTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,871,100 Walton Aug. 9, 1932 2,371,579 C'ole et al Mar. 13, 1945 

